1. Field of the Invention:
This invention relates to a method for the continuous determination of the concentration of a carbonate or sulfite, or both in a liquid, or more specifically in a solution or slurry.
2. Description of the Prior Art:
An absorbent slurry in an apparatus for liquid purification or desulfurization according to the wet lime process is a typical example of a liquid containing a carbonate and a sulfite. It is usual practice to control the desulfurizing capacity of such an apparatus by checking the pH level of a liquid being recirculated in an absorption tower and supplying an absorbent to keep the pH value of the liquid at a level which enables the apparatus to maintain its normal desulfurizing capacity.
The recent trend toward the saving of resources and energy has been calling for an improvement in the efficiency of a boiler or like apparatus forming a source of exhaust gas, and an increase in the speed at which its load is varied. This has given rise to the requirement for an apparatus for the desulfurization of such exhaust gas to be capable of working in harmony with any such change in the load of a boiler or like apparatus without lowering its desulfurizing capacity.
The pH control for the liquid in the absorption tower is hereinabove described, however, makes it difficult for the desulfurizing apparatus to maintain its satisfactory desulfurizing capacity for a prolonged period of time irrespective of a rapid change in the load of a boiler or like apparatus. This is due to the fact that the concentration of a carbonate and a sulfite in the absorbent slurry varies with a change in the load of desulfurization, even if the pH value of the liquid in the absorption tower may be controlled at a constant level. It is, therefore, essential to determine the concentration of a carbonate and a sulfite in the absorbent slurry in order to maintain the capacity of the desulfurizing apparatus at a satisfactory level irrespective of any such change in the load.